1. Field of the Invention
The present invention generally relates to an apparatus for printing a color image by combining three different colors with each other. More specifically, the present invention is directed to a color image printing apparatus capable of printing a high-quality color image by eliminating a Moire pattern.
2. Description of the Related Art
Conventionally, color thermal printers are known as color printing apparatuses. In the conventional color thermal printer, the color ink ribbons colored by various color ink such as cyan (C), magenta (M), and yellow (Y) are depressed to the recording (printing) paper by using the thermal printing head, and then the respective color ink of these ink ribbons is thermally transferred to the printing paper, thereby performing the color printing operation.
More specifically, in accordance with this conventional color printing system, the cyan (C) ink is first transferred to the printing paper, and thereafter the magenta (M) ink is transferred to the same position of this printing paper, where the cyan ink has been transferred, and finally the yellow (Y) ink is transferred to the same position in order to print out a desired color image.
However, in this type of color printing apparatus, the respective color ink is not correctly transferred to a preselected transfer position, because of positional shifts (deviation) caused by the mechanical factors of the color printing apparatus, and further because of the heat storage effects of the heating resistive elements employed in the thermal printing head. As a result, a very small positional shift is produced in the respective color dots, so that color deviation of a color image occurs and a Moire pattern is produced.